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<div class="fragment"><div class="line"><a name="l00001"></a><span class="lineno">    1</span>&#160;<span class="comment">/*</span></div><div class="line"><a name="l00002"></a><span class="lineno">    2</span>&#160;<span class="comment">  FUSE: Filesystem in Userspace</span></div><div class="line"><a name="l00003"></a><span class="lineno">    3</span>&#160;<span class="comment">  Copyright (C) 2001-2007  Miklos Szeredi &lt;miklos@szeredi.hu&gt;</span></div><div class="line"><a name="l00004"></a><span class="lineno">    4</span>&#160;<span class="comment"></span></div><div class="line"><a name="l00005"></a><span class="lineno">    5</span>&#160;<span class="comment">  Utility functions for setting signal handlers.</span></div><div class="line"><a name="l00006"></a><span class="lineno">    6</span>&#160;<span class="comment"></span></div><div class="line"><a name="l00007"></a><span class="lineno">    7</span>&#160;<span class="comment">  This program can be distributed under the terms of the GNU LGPLv2.</span></div><div class="line"><a name="l00008"></a><span class="lineno">    8</span>&#160;<span class="comment">  See the file COPYING.LIB</span></div><div class="line"><a name="l00009"></a><span class="lineno">    9</span>&#160;<span class="comment">*/</span></div><div class="line"><a name="l00010"></a><span class="lineno">   10</span>&#160;</div><div class="line"><a name="l00011"></a><span class="lineno">   11</span>&#160;<span class="preprocessor">#include &quot;config.h&quot;</span></div><div class="line"><a name="l00012"></a><span class="lineno">   12</span>&#160;<span class="preprocessor">#include &quot;<a class="code" href="fuse__lowlevel_8h.html">fuse_lowlevel.h</a>&quot;</span></div><div class="line"><a name="l00013"></a><span class="lineno">   13</span>&#160;<span class="preprocessor">#include &quot;fuse_i.h&quot;</span></div><div class="line"><a name="l00014"></a><span class="lineno">   14</span>&#160;</div><div class="line"><a name="l00015"></a><span class="lineno">   15</span>&#160;<span class="preprocessor">#include &lt;stdio.h&gt;</span></div><div class="line"><a name="l00016"></a><span class="lineno">   16</span>&#160;<span class="preprocessor">#include &lt;string.h&gt;</span></div><div class="line"><a name="l00017"></a><span class="lineno">   17</span>&#160;<span class="preprocessor">#include &lt;signal.h&gt;</span></div><div class="line"><a name="l00018"></a><span class="lineno">   18</span>&#160;<span class="preprocessor">#include &lt;stdlib.h&gt;</span></div><div class="line"><a name="l00019"></a><span class="lineno">   19</span>&#160;</div><div class="line"><a name="l00020"></a><span class="lineno">   20</span>&#160;<span class="keyword">static</span> <span class="keyword">struct </span>fuse_session *fuse_instance;</div><div class="line"><a name="l00021"></a><span class="lineno">   21</span>&#160;</div><div class="line"><a name="l00022"></a><span class="lineno">   22</span>&#160;<span class="keyword">static</span> <span class="keywordtype">void</span> exit_handler(<span class="keywordtype">int</span> sig)</div><div class="line"><a name="l00023"></a><span class="lineno">   23</span>&#160;{</div><div class="line"><a name="l00024"></a><span class="lineno">   24</span>&#160;        <span class="keywordflow">if</span> (fuse_instance) {</div><div class="line"><a name="l00025"></a><span class="lineno">   25</span>&#160;                <a class="code" href="fuse__lowlevel_8h.html#a198429f3fbc23ef29ef9971271827690">fuse_session_exit</a>(fuse_instance);</div><div class="line"><a name="l00026"></a><span class="lineno">   26</span>&#160;                <span class="keywordflow">if</span>(sig &lt;= 0) {</div><div class="line"><a name="l00027"></a><span class="lineno">   27</span>&#160;                        fprintf(stderr, <span class="stringliteral">&quot;assertion error: signal value &lt;= 0\n&quot;</span>);</div><div class="line"><a name="l00028"></a><span class="lineno">   28</span>&#160;                        abort();</div><div class="line"><a name="l00029"></a><span class="lineno">   29</span>&#160;                }</div><div class="line"><a name="l00030"></a><span class="lineno">   30</span>&#160;                fuse_instance-&gt;error = sig;</div><div class="line"><a name="l00031"></a><span class="lineno">   31</span>&#160;        }</div><div class="line"><a name="l00032"></a><span class="lineno">   32</span>&#160;}</div><div class="line"><a name="l00033"></a><span class="lineno">   33</span>&#160;</div><div class="line"><a name="l00034"></a><span class="lineno">   34</span>&#160;<span class="keyword">static</span> <span class="keywordtype">void</span> do_nothing(<span class="keywordtype">int</span> sig)</div><div class="line"><a name="l00035"></a><span class="lineno">   35</span>&#160;{</div><div class="line"><a name="l00036"></a><span class="lineno">   36</span>&#160;        (void) sig;</div><div class="line"><a name="l00037"></a><span class="lineno">   37</span>&#160;}</div><div class="line"><a name="l00038"></a><span class="lineno">   38</span>&#160;</div><div class="line"><a name="l00039"></a><span class="lineno">   39</span>&#160;<span class="keyword">static</span> <span class="keywordtype">int</span> set_one_signal_handler(<span class="keywordtype">int</span> sig, <span class="keywordtype">void</span> (*handler)(<span class="keywordtype">int</span>), <span class="keywordtype">int</span> <span class="keyword">remove</span>)</div><div class="line"><a name="l00040"></a><span class="lineno">   40</span>&#160;{</div><div class="line"><a name="l00041"></a><span class="lineno">   41</span>&#160;        <span class="keyword">struct </span>sigaction sa;</div><div class="line"><a name="l00042"></a><span class="lineno">   42</span>&#160;        <span class="keyword">struct </span>sigaction old_sa;</div><div class="line"><a name="l00043"></a><span class="lineno">   43</span>&#160;</div><div class="line"><a name="l00044"></a><span class="lineno">   44</span>&#160;        memset(&amp;sa, 0, <span class="keyword">sizeof</span>(<span class="keyword">struct</span> sigaction));</div><div class="line"><a name="l00045"></a><span class="lineno">   45</span>&#160;        sa.sa_handler = <span class="keyword">remove</span> ? SIG_DFL : handler;</div><div class="line"><a name="l00046"></a><span class="lineno">   46</span>&#160;        sigemptyset(&amp;(sa.sa_mask));</div><div class="line"><a name="l00047"></a><span class="lineno">   47</span>&#160;        sa.sa_flags = 0;</div><div class="line"><a name="l00048"></a><span class="lineno">   48</span>&#160;</div><div class="line"><a name="l00049"></a><span class="lineno">   49</span>&#160;        <span class="keywordflow">if</span> (sigaction(sig, NULL, &amp;old_sa) == -1) {</div><div class="line"><a name="l00050"></a><span class="lineno">   50</span>&#160;                perror(<span class="stringliteral">&quot;fuse: cannot get old signal handler&quot;</span>);</div><div class="line"><a name="l00051"></a><span class="lineno">   51</span>&#160;                <span class="keywordflow">return</span> -1;</div><div class="line"><a name="l00052"></a><span class="lineno">   52</span>&#160;        }</div><div class="line"><a name="l00053"></a><span class="lineno">   53</span>&#160;</div><div class="line"><a name="l00054"></a><span class="lineno">   54</span>&#160;        <span class="keywordflow">if</span> (old_sa.sa_handler == (<span class="keyword">remove</span> ? handler : SIG_DFL) &amp;&amp;</div><div class="line"><a name="l00055"></a><span class="lineno">   55</span>&#160;            sigaction(sig, &amp;sa, NULL) == -1) {</div><div class="line"><a name="l00056"></a><span class="lineno">   56</span>&#160;                perror(<span class="stringliteral">&quot;fuse: cannot set signal handler&quot;</span>);</div><div class="line"><a name="l00057"></a><span class="lineno">   57</span>&#160;                <span class="keywordflow">return</span> -1;</div><div class="line"><a name="l00058"></a><span class="lineno">   58</span>&#160;        }</div><div class="line"><a name="l00059"></a><span class="lineno">   59</span>&#160;        <span class="keywordflow">return</span> 0;</div><div class="line"><a name="l00060"></a><span class="lineno">   60</span>&#160;}</div><div class="line"><a name="l00061"></a><span class="lineno">   61</span>&#160;</div><div class="line"><a name="l00062"></a><span class="lineno"><a class="line" href="fuse__common_8h.html#a292dccc3c7b1799cb054efa2ba0c774b">   62</a></span>&#160;<span class="keywordtype">int</span> <a class="code" href="fuse__common_8h.html#a292dccc3c7b1799cb054efa2ba0c774b">fuse_set_signal_handlers</a>(<span class="keyword">struct</span> fuse_session *se)</div><div class="line"><a name="l00063"></a><span class="lineno">   63</span>&#160;{</div><div class="line"><a name="l00064"></a><span class="lineno">   64</span>&#160;        <span class="comment">/* If we used SIG_IGN instead of the do_nothing function,</span></div><div class="line"><a name="l00065"></a><span class="lineno">   65</span>&#160;<span class="comment">           then we would be unable to tell if we set SIG_IGN (and</span></div><div class="line"><a name="l00066"></a><span class="lineno">   66</span>&#160;<span class="comment">           thus should reset to SIG_DFL in fuse_remove_signal_handlers)</span></div><div class="line"><a name="l00067"></a><span class="lineno">   67</span>&#160;<span class="comment">           or if it was already set to SIG_IGN (and should be left</span></div><div class="line"><a name="l00068"></a><span class="lineno">   68</span>&#160;<span class="comment">           untouched. */</span></div><div class="line"><a name="l00069"></a><span class="lineno">   69</span>&#160;        <span class="keywordflow">if</span> (set_one_signal_handler(SIGHUP, exit_handler, 0) == -1 ||</div><div class="line"><a name="l00070"></a><span class="lineno">   70</span>&#160;            set_one_signal_handler(SIGINT, exit_handler, 0) == -1 ||</div><div class="line"><a name="l00071"></a><span class="lineno">   71</span>&#160;            set_one_signal_handler(SIGTERM, exit_handler, 0) == -1 ||</div><div class="line"><a name="l00072"></a><span class="lineno">   72</span>&#160;            set_one_signal_handler(SIGPIPE, do_nothing, 0) == -1)</div><div class="line"><a name="l00073"></a><span class="lineno">   73</span>&#160;                <span class="keywordflow">return</span> -1;</div><div class="line"><a name="l00074"></a><span class="lineno">   74</span>&#160;</div><div class="line"><a name="l00075"></a><span class="lineno">   75</span>&#160;        fuse_instance = se;</div><div class="line"><a name="l00076"></a><span class="lineno">   76</span>&#160;        <span class="keywordflow">return</span> 0;</div><div class="line"><a name="l00077"></a><span class="lineno">   77</span>&#160;}</div><div class="line"><a name="l00078"></a><span class="lineno">   78</span>&#160;</div><div class="line"><a name="l00079"></a><span class="lineno"><a class="line" href="fuse__common_8h.html#aeb674bbc11074c4fe520b952d6bfdd30">   79</a></span>&#160;<span class="keywordtype">void</span> <a class="code" href="fuse__common_8h.html#aeb674bbc11074c4fe520b952d6bfdd30">fuse_remove_signal_handlers</a>(<span class="keyword">struct</span> fuse_session *se)</div><div class="line"><a name="l00080"></a><span class="lineno">   80</span>&#160;{</div><div class="line"><a name="l00081"></a><span class="lineno">   81</span>&#160;        <span class="keywordflow">if</span> (fuse_instance != se)</div><div class="line"><a name="l00082"></a><span class="lineno">   82</span>&#160;                fprintf(stderr,</div><div class="line"><a name="l00083"></a><span class="lineno">   83</span>&#160;                        <span class="stringliteral">&quot;fuse: fuse_remove_signal_handlers: unknown session\n&quot;</span>);</div><div class="line"><a name="l00084"></a><span class="lineno">   84</span>&#160;        <span class="keywordflow">else</span></div><div class="line"><a name="l00085"></a><span class="lineno">   85</span>&#160;                fuse_instance = NULL;</div><div class="line"><a name="l00086"></a><span class="lineno">   86</span>&#160;</div><div class="line"><a name="l00087"></a><span class="lineno">   87</span>&#160;        set_one_signal_handler(SIGHUP, exit_handler, 1);</div><div class="line"><a name="l00088"></a><span class="lineno">   88</span>&#160;        set_one_signal_handler(SIGINT, exit_handler, 1);</div><div class="line"><a name="l00089"></a><span class="lineno">   89</span>&#160;        set_one_signal_handler(SIGTERM, exit_handler, 1);</div><div class="line"><a name="l00090"></a><span class="lineno">   90</span>&#160;        set_one_signal_handler(SIGPIPE, do_nothing, 1);</div><div class="line"><a name="l00091"></a><span class="lineno">   91</span>&#160;}</div><div class="ttc" id="fuse__lowlevel_8h_html_a198429f3fbc23ef29ef9971271827690"><div class="ttname"><a href="fuse__lowlevel_8h.html#a198429f3fbc23ef29ef9971271827690">fuse_session_exit</a></div><div class="ttdeci">void fuse_session_exit(struct fuse_session *se)</div><div class="ttdef"><b>Definition:</b> <a href="fuse__lowlevel_8c_source.html#l03037">fuse_lowlevel.c:3037</a></div></div>
<div class="ttc" id="fuse__common_8h_html_a292dccc3c7b1799cb054efa2ba0c774b"><div class="ttname"><a href="fuse__common_8h.html#a292dccc3c7b1799cb054efa2ba0c774b">fuse_set_signal_handlers</a></div><div class="ttdeci">int fuse_set_signal_handlers(struct fuse_session *se)</div><div class="ttdef"><b>Definition:</b> <a href="fuse__signals_8c_source.html#l00062">fuse_signals.c:62</a></div></div>
<div class="ttc" id="fuse__common_8h_html_aeb674bbc11074c4fe520b952d6bfdd30"><div class="ttname"><a href="fuse__common_8h.html#aeb674bbc11074c4fe520b952d6bfdd30">fuse_remove_signal_handlers</a></div><div class="ttdeci">void fuse_remove_signal_handlers(struct fuse_session *se)</div><div class="ttdef"><b>Definition:</b> <a href="fuse__signals_8c_source.html#l00079">fuse_signals.c:79</a></div></div>
<div class="ttc" id="fuse__lowlevel_8h_html"><div class="ttname"><a href="fuse__lowlevel_8h.html">fuse_lowlevel.h</a></div></div>
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